I read that the male deposits his semen on a web pad and then uses his palpi to pick up the semen and transfer it to the female. I was under the impression that all animals have the instinct to have sex/reproduce because it feels good. But it seems to me that spider sex doesn't feel particularly good for the spiders--not that it feels bad, but that it's nothing special. It seems that way to me because I thought the palpi were simply a part of the leg and not sexual organs.

1. So, if mating doesn't feel good, what drives them to do it? How could this behavior have evolved? (That is, if I'm correct in my assessment that it doesn't feel good).

2. Are there other animals/any animals for which mating doesn't feel good?

Another possibility I thought of: maybe the act of depositing semen is what feels good. If that's it, then where's his incentive to pick up his semen and give it to the female?

Sorry if my questions seems elementary to any experts here--I'm very new at this! And thanks a bunch for any answers!

I'm well aware that certain life forms don't have the "feel good" incentive to reproduce--plants and bacteria are obvious examples. But spiders are a higher life form than plants or bacteria. While they don't do algebra or teach their young to read, they must have their motivation to participate in certain behaviors. And that's what I was asking about.

I came here looking for some answers because I am curious--that's not a sign of an idiot. It's a characteristic of someone who wants to learn and expand the base of knowledge. The quest for knowledge is something that should be encouraged. I had no idea that I would get such a condescending answer, basically telling me I'm stupid for asking.

OK spiders can be considered 'higher' life forms than plants or bacteria for our purposes. But they don't even have what we would class as a brain - just a vague aggregation of cells that pretty much does the same job.

The fact is, if they didn't reproduce, there would be no spiders. Those that only mated because it 'felt good' would go extinct (because using a limb to wipe some sperm on your mate, or whatever they have, isn't sensual by anyone's standards....er hang on lol) - those that mated because of some other, more basic, drive would propagate and this is what we see in the cobwebs today.

Ok, so humans mate because it feels good, but I imagine many people would argue that there is some underlying drive which we can't explain as well. Dolphins and Monkeys are known to mate just for the sake of pleasure, even using contraception in one form or another.

I think we're being very short-sighted on our definition of "feels good." In the case of many animals, there isn't the sort of physical feedback that mammals have, but there is an instinctive compulsion that needs to be satisfied.

Even in humans - if you felt the compulsion to, say, check to see if the oven is on, would checking make you feel good-? You've relieved a compulsion, but the relief isn't physical.

I have another question. I was told by someone that spiders only mate once in their lives, but I know that some spiders live a very long time (twenty years is possible for a tarantula). Is it true that even a very long-lived spider only mates once? That seems such a waste. At what age does a tarantula mate?

It depends on the spider. Often, the palp used to transfer the sperm packet breaks off, which makes another mating hard to accomplish (they'll still try, though). I'm pretty sure that, unlike insects, long-lived spiders continue to molt even as adults (I didn't look this up, so I may be wrong), so it seems like the males would regenerate the palps.